CAREER: Coherent Phonon Control in Iron-Based Superconductors

职业：铁基超导体中的相干声子控制

• 批准号: 1944957
• 负责人: Wanzheng Hu
• 金额: $ 63.08万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1944957&HistoricalAwards=false
• 关键词: CAREER; Coherent; Phonon; Control; Iron

Nontechnical Abstract: High-temperature superconductivity is a remarkable phenomenon found in quantum materials. To understand and control superconductivity is the key to next-generation devices to handle information or harvest energy. The physical properties of high-temperature superconductors are extremely sensitive to their crystal structures. Tailored laser pulses can selectively control structural features which are crucial for materials properties. In certain cases, laser excitation can create crystal structures hosting novel functionalities which are impossible to achieve by other methods. This research uses tailored laser pulses to optically engineer the structure of iron-based superconductors. The goal is to advance our knowledge on the relation between crystal structure and high-temperature superconductivity, and to identify the most efficient knob to control superconductivity. This project also includes broad education and outreach programs for female graduate students in physics, local female high school students, and K-12 students. These activities aim at inspiring excitement about experimental physics, and helping students to recognize opportunities for future education and academic careers in materials science.Technical Abstract: Controlling the physical properties of quantum materials along non-invasive and ultrafast pathways is the key for developing next-generation devices. Small structural perturbations created by laser excitation of phonons can directly and selectively modify structural parameters which are crucial to the physical properties of quantum materials. This project aims at optically investigate and manipulate superconductivity and competing orders in iron-based superconductors by modulating the iron-arsenic/selenium distance. The project uses long-wavelength laser excitation directly targets lattice modes which control the iron-arsenic/selenium distance to realize novel phases which do not exist at equilibrium. A desirable outcome of this approach is stabilizing transient superconductivity at high temperatures. This research will advance our knowledge on the relevant degrees of freedom that can be tuned, and novel and exotic phases which can be generated by coherent terahertz fields. The methods used for iron-based superconductors can be applied to a broad category of materials including cuprates, ferroelectrics and multiferroics to identify the most efficient knob to steer quantum materials to desired phases. The research also has industry impacts on the development of next-generation optoelectronic devices, such as superconducting devices which can be optically engineered using coherent terahertz radiation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

摘要：高温超导现象是量子材料中的一种重要现象。理解和控制超导性是下一代设备处理信息或收集能量的关键。高温超导体的物理性质对其晶体结构极为敏感。定制的激光脉冲可以选择性地控制对材料性能至关重要的结构特征。在某些情况下，激光激发可以产生具有新功能的晶体结构，这是其他方法无法实现的。这项研究使用定制的激光脉冲来光学工程铁基超导体的结构。目的是提高我们对晶体结构与高温超导之间关系的认识，并确定最有效的控制超导的旋钮。该项目还包括针对物理学女研究生、当地女高中生和K-12学生的广泛教育和推广计划。这些活动旨在激发学生对实验物理的兴趣，并帮助学生认识到未来材料科学教育和学术生涯的机会。技术摘要：沿非侵入和超快路径控制量子材料的物理特性是开发下一代器件的关键。由激光激发声子产生的微小结构扰动可以直接和选择性地改变对量子材料物理性质至关重要的结构参数。该项目旨在通过调节铁砷/硒的距离来光学研究和操纵铁基超导体中的超导性和竞争顺序。该项目利用长波激光激发直接瞄准控制铁砷/硒距离的晶格模式，以实现不存在于平衡态的新相。这种方法的一个理想结果是在高温下稳定瞬态超导性。这项研究将提高我们对相关的可调谐自由度的认识，以及相干太赫兹场可以产生的新颖和奇异相位。用于铁基超导体的方法可以应用于包括铜酸盐、铁电体和多铁材料在内的广泛材料类别，以确定将量子材料导向所需相的最有效旋环。该研究还对下一代光电器件的发展产生了行业影响，例如可以使用相干太赫兹辐射进行光学工程的超导器件。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。